1. Field of the Invention
The present invention relates to a connector provided with a locking function.
2. Description of the Related Art
A known connector with a locking function is disclosed in Japanese Unexamined Patent Publication No. 6-20740, and also is shown in FIGS. 7 and 8 herein. The prior art connector of FIGS. 7 and 8 includes first and second housings 101 and 103. A locking projection 102 is formed on the upper surface of the first housing 101 and a lock arm 104 is formed on the upper surface of the second housing 103. The lock arm 104 can be deformed elastically to move over the locking projection 102 as the housings 101 and 103 are being connected. However, the lock arm 104 is restored elastically to its original shape when the housings 101 and 103 are connected properly. A locking portion 104A is formed at the leading end of the lock arm 104 and engages the locking projection 102 to lock the housings 101 and 103 together, as shown in FIG. 8. The bottom end of the locking portion 104A strikes the upper surface of the mating housing 101 with a sound upon the elastic restoration of the lock arm 104. This striking sound informs the operator that the lock arm 104 has locked the housings 101 and 103 together.
In the above-described prior art connector, as the height of the locking projection 102 increases, a projecting distance of the locking portion 104A is lengthened accordingly so that the locking portion 104A can strike the upper surface of the mating housing 101. However, as the projecting distance of the locking portion 104A increases, a degree of elastic deformation of the lock arm 104 also increases. As a result, a connection resistance resulting from the elastic force of the lock arm 104 disadvantageously increases.
The present invention was developed in view of the above problem, and an object thereof is to reduce a degree of elastic deformation of a lock arm while maintaining a striking sound at the completion of a locking operation.
The subject invention is directed to a connector that comprises first and second housings that are at least partly connectable with each other. A locking projection is formed on the first housing and a lock arm is formed of the second housing. The lock arm contacts the locking projection during connection of the housings and deforms elastically to pass the locking projection. The lock arm then is restored elastically substantially to its original shape to engage the locking projection and to lock the housings together. This elastic restoration causes the lock arm to strike the second housing and to produce a striking sound when the housings are connected properly with each other.
The lock arm comprises a lock for interfering with the locking projection and generating deflection of the lock arm during the connection of the housings. The lock then engages the locking projection when the housings are connected properly with each other.
At least one striking portion is located in a non-interfering position where it does not interfere with the locking projection. The striking portion is dimensioned and disposed to strike one of the housings when the housings are properly connected with each other. A projecting distance of the locking portion is set shorter than that of the striking portion.
The striking portion and the lock are at separate locations, and the projecting distance of the lock is smaller than the projecting distance of the striking portion. Thus, a degree of elastic deformation of the lock arm can be decreased to reduce a connection resistance resulting from an elastic force of the lock arm without reducing the ability to produce a striking sound.
Preferably, two striking portions are formed substantially symmetrically with respect to the longitudinal axis of the lock arm. The symmetrical disposition of the striking portions prevents a twisting deformation at the time of striking.
The striking portion preferably is substantially continuous with the lock. The continuous formation of the locking and striking portions prevents deformation of the lock in response to forces that act in directions to separate the housings.
According to a further preferred embodiment, the projecting distance of the lock is set such that the lock arm interacts only with an upper portion of the locking projection. As a result, the displacement of the lock arm caused by interaction with the locking projection is reduced. Accordingly, a connection resistance resulting from the elastic restoring force of the lock arm is reduced.
The connector may further comprise a slider that is movable in the second housing. The slider restricts movement of the lock arm, when the slider is in a displacement restricting position, but allows movement of the lock arm, when the slider is in a displacement permitting position. The slider may have a flexible wall for contacting the lock arm to effect an unlocking of the lock arm, when the slider is moved to the displacement permitting position and when the two housings are locked.
Most preferably, the connector further comprises biasing means for biasing the two housings in a disengaging direction with respect to each other.
These and other objects, features and advantages of the present invention will become apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings.